Three Twin Cities nurses who crossed their union's picket line during a mass walkout June 10 say they were harassed by the union after the fact through letters calling them to a disciplinary hearing.

The nurses, all from Children's Hospitals and Clinics of Minnesota, say they resigned from the union before the 24-hour walkout in order to work behind the picket lines. Nonetheless, they received letters from the Minnesota Nurses Association saying they may be subject to reprimand, censure or expulsion.

The three are Maria Ruhl, Karen Hermann and Mary Sue Moe.

"I just want it all to go away, and now they're stirring the pot up again," Ruhl said of the letter, received Saturday.

The nurses filed a complaint against the MNA late Wednesday with the National Labor Relations Board. In the past, it's been the MNA that's filed a flurry of federal complaints against the nurses' employers.

About 12,000 MNA members staged a 24-hour walkout June 10 after unusually contentious bargaining broke down with 14 Twin Cities hospitals. They were gearing up for an open-ended strike when negotiators reached a last-minute settlement July 1.

The hospitals are owned by Allina, Fairview, Children's, Park Nicollet, HealthEast and North Memorial.

Since the settlement, the MNA has sent letters to 77 nurses for working behind the picket line, spokesman John Nemo said. "A handful" of letters, he said, were mistakenly sent to those who had quit the union.

The union had received a total of 220 resignations during the protracted contract negotiations, he added.

Ruhl said that as the June 10 strike approached, "I could not in good conscience abandon my patients." She resigned June 9 and worked during the strike. Since then, she said, some nurses who supported the strike have refused to look her in the eye or speak to her at work.

Karen Hermann, who also received a letter Saturday, said she almost had an accident when her husband read the letter to her as she was driving home from work.

"I said, 'You've got to be kidding me!' My blood pressure -- I can't tell you how high it went," she said.

The nurses are getting free legal assistance from the National Right to Work Foundation.

Because they resigned before the strike, "the union has no power to fire them or discipline them or bring them up on charges," said Glenn Taubman, a lawyer for the Springfield, Va.-based group. "They are blatantly doing it to harass or try to intimidate the nurses who wouldn't toe the line."

Nemo said the MNA has yet to receive any formal complaints from the NLRB.

"It was not the MNA's intent to send any of these letters to non-MNA or non-union nurses, and we apologize if in fact that did occur," he said, adding that those nurses would receive follow-up letters from the MNA.